The Skill of Classification
At its simplest, classifying means organizing objects by their similar or dissimilar characteristics. The process of classifying helps children obtain information about the world around them, as well as developing thinking and reasoning abilities.
Classifying can start as early as toddlerhood, when a child might put all the blue blocks, red blocks, and yellow blocks in their respective piles. They might not even know the word for each color yet, but they can observe the differences between them.
“One of these things is not like the other”, goes the famous Sesame Street song, and children are extremely adept at picking out things that just don’t fit. Think about what they have to do to figure out these kinds of puzzles: first, they must decide what universal attribute the majority of the items share, and then they must decide which item doesn’t fit the pattern. It’s a two-step process.
Classification becomes more sophisticated when children begin to notice that items can share some attributes but differ in others. For instance, buttons could be sorted by color or shape. Regrouping a collection of objects can strengthen a child’s ability to closely observe and organize according to specific characteristics.
Younger children are usually focused on very obvious characteristics, like color, size, and shape. Examples of these activities include button or bead sorting; small, medium, and large; and shape sorters where only the correct shape will fit through each hole. More advanced classification work includes living/non-living, land/air/water, and fruit/vegetable.
An older child will begin to look at objects with more discrimination: they may notice that while oranges, lemons, and limes are different in color, they are all citrus fruits. Or they may realize that insects, while varying widely in appearance, all have three body parts and six legs. Montessori for Everyone